Electkic snap switch



(No Model.) 2 sneetssheet 1.

G. W. HART. ELECTRIC SNAP SWITCH.

No, 447,728. Y Patented Mar. 3, 1891.

lgLmL-:mwmjglm 2.'....41241111mlm-3212? Wi V g @M fw@ T sheets-sheet 2 (No Model.)

G. W. HART. ELECTRIC SNAP SW1-TCH.

No. 447,728. Patented Mar. 3, 1891.

me mms versus co., Moro-umn., wAsNmnron, n. c.

NTTED STATES PATENT OFFICE.d

GERALD 1V. HART, OF KANSAS CITY, MISSOURI, ASSIGNO OF ONE-HALF TO GEORGE S. HEGEMAN, OF SAME PLACE.

ELECTRIC SNAP-SWITCH.

SPECIFICATION forming part of Letters Patent N o. 447,728, dated March 3, 1891. Application led August 2l, 1890. Serial No. 362,648. (No model.)

To a/ZZ whom it may concern:

Be it known that I, GERALD 1V. HART, a citizen of the United States, residing at Kansas Oity, in the county of Jackson and State of Missouri, have invented certain new and useful Improvements in Electric Snap- Switches, of which the following is a specification.

My invention relates to improvements in electric snap-switches; and the object of my improvement is simplicity of construction and general efficiency.

In the accompanying drawings, Figure 1 is a plan view of my switch with the cap-plate and thumb-turn removed. Fig. 2 is a side elevation of my switch with the cap in vertical section. Fig. 3 is an enlarged vertical section on the line x 00 of Fig. 1 of a portion of the base, the cam-plate and switch-plate, the other parts being shown in side elevation. Fig. 4 is an enlarged plan view of the switch-plate; Fig. 5, an enlarged plan view of the camplate; Fig. G, an enlarged reverse plan View of the spring-plate and spring. Fig. 7 is an enlarged horizontal section on a line below the spring-plate and above the spring, the cams of the cam-plate underneath being indicated by broken lines; and Fig. 3 is a like view of the same, with the spring moved into the position where it is just ready to pass the point of one cam.

A designates the base, and B the cap, which conceals and protects the working parts of the switch with the exception of the thumlo-turn a.

b b designate the contact-plates secured to the base A and provided with contact-pieces or brushes 9 and screws 10 for the attachment of the wires 11 11, between which the connections are to be made or'broken.

12 designates a cam-plate having a hub 13 in its center, which forms a bearing for the shaft 14, to which the thu mb-turn a is secured. The upper part of the cam-plate 12 is chambered, so as to form four cams 15, vthe point of each cam bein-g followed bya let-off or incline 1G, as shown most clearly in Fig. 5. The spring-plate c is rigidly secured to the shaft 14 near its upper end, so as to rotate therewith. Said plate is slotted obliquely, as at 17, and provided on its upper side with a lever or link 1S, pivoted to said plate by the pin 19. The opposite end of said link is provided with a swinging stud 20, which passes through the slot 17 downwardly to a point inside the cam-plate, where its end is preferably provided with a friction-roller 21, although, if desired, it may have direct Contact with said cam-plate. The spring-plate is prog vided with a stud or pin 22, fixed to said plate, and any suitable spring, preferably a leaf- 6o spring 23, is arranged on the studs or pins 2O and 22 with a constant tendency to force said studs apart.

Interposed between the camplate and the spring-plate and its spring is the switch-plate d. This plate is loosely mounted on the shaft 14, so as to turn freely thereon, while it is centered and held in position by said shaft, the shaft being shouldered just above said plate. The switch-plate d is provided with a 7o slot 24, whose slant or incline is substantially the same as that of the cams 15 and transversely to that of the 1etoff or incline 16 of the cam-plate. The slot in the spring-plate is transversely to that inthe switch-plate, and substantially coincideswith the let-off or inclines 16 of the cam-plate. The swinging stud 2O on the link of the spring-plate passes through said slot 24. The switch-plate is provided with contacts 25 at its opposite ends 8c for engaging the contact-pieces or brushes 9. The thumb-turn, for convenience of application, may be fitted to the shaft 14 by means of an internally-threaded hub and screwed upon the end of said shaft. Upon turning the 8 5 shaft through the thumb-turn the springplate moves with it, thereby partially revolving the entire spring. As the spring-plate and spring thus move along, the swinging stud rides up the edge of one of the cams, 9o moving the stud inwardly in the slots of the spring-plate and switch-plate. The switchplate remains stationary until the lower end of the swinging stud passes the point of the cam. Fig. S illustrates the switch when this stud is nearly ready to pass the point of one cam. As soon as the stud passes the point of the cam, the tendency of the spring to move the studs 2O and 22 apart moves the swinging stud rapidly along the let-off or incline 16 into the Ioo notch or recess formed by the junction of said incline and the next succeeding com, the position of the parts at this time being.` indicated by the broken lines in Fig'. S. As soon is the 5 swinging si ud 2O snaps down the incline 0r let-olif, its motion is transversely to the slot in the switclvplnte, und consequently it carries the switch-plate with it as it thus snaps off the peint of the cmn. There beingfour cams, the switch-plate stops after having made t qutiter-revolution, and if the motion of the shaft is continued to carry the roller and stud 2O by the next succeeding` com the switchplate will be moved another quarter-revolutien, :1nd so on repeatedly whenever the shaft is turned, thus Closing er opening the circuit, as may be desired, by stopping the switchplnte when its contact-pieces are in or out of Contact with the contact-pieces or brushes 9.

I claim as my inveutionl. The combination of the cam-platte having @inns l5 and let-offs or inclines '1G with the slotted switch-plate, swing-plate, the spring', :ind the stud 20, carried by said springpluto und engaging' said switch-platte :ind Canis, substantially as described, and for the purpose speciiied.

2. The combination of the shaft, the springplaie mounted to revolve with the smne and slotted` :is described, the stud or pin 22, fixed on said spring-plate for one end of the spring, and the pivoted link carried by said springplate, .fi swinging stud at the outer end of said link, a spring connected to said studs with a constant tendency to force them apart, the slotted switch-plate having the swinging stud extended through its slot, and the earn-plate for engaging the lower end of said swinging stud, substantially as described, and for the purpose specified.

GERALD lV. HART.

W it n esses:

JAMES SHEPARD, JOHN Emvfxnns, J1'. 

